Don’t even talk yourself down about how this is boring....I came here because I needed some help and you did a better job than any other video I’ve watched and I appreciate your time for that, this video is older but I never needed anything like this until now, but this was easily one of the best transistor-fix videos out there, very, very clear and I learned quite a bit from your video. Thank you

The way you explained how a transistor amplifies a signal was spot on. Thanks for this video, you are a natural teacher ..😊

I am working on an old amplifier, and this is the best information I have found to trouble shoot a dead channel...

Some folks are just good at breaking down complicated thing so others can understand them, it’s a gift 👍🏻👍🏻

Just watched one video on fixing broken amps which was useless and longer, then I came here and found what I needed to understand. Thanks a lot. I've been quoted $500 to fix my amp. I could buy a new car for that.

Hi, I am very grateful for your video. You may not realise, but you have given some very important information about how things work which are missing in other electronic repair videos. As a hobbyist, I have learnt a lot from you. Thank you.

Very good and clear explanation of how a transistor works and how to diagnose a bad output transistor.

Wasn't boring at all. I made very good use of it and replaced power transistors on an old, but solid built power amp. So, thank you for sharing.

Definitely, the explanation here on the issue of replacing power transistors will be the best I have ever seen, including some aspects that may be less clear to most people not trained in this activity.

That was possibly the best explanation of the workings of a transisteor and an amplifier I've ever seen in my 5 decades.

DUDE!!! Thank you!! I sincerely appreciate your time. I've been trying an hour per day for FIVE months now to figure out how to fix my Pops amp. He passed a couple years back and this thing is pretty much all I have that lets me feel like we're still hangin' together and jammin' ... then it croaked about 6 months ago ... well at least one channel did. I knew it was one of the damned little transistor thingys after watching so many vid's and reading so much, but this was the FIRST one that I actually understood what those 3 stupid leg thingys do and why and how to work forward or back to find the other crap they screwed up along the way, so I can FINALLY rock out with Pops again ... well in spirit anyways ... and ashes too, a bit of em anyways I put in a glass thingy I glued to the top of the sub so he can still dance to the "tight bass response" of his Onkyo he always talked about, whatever the hell that means. I just know it sounds killer when it's working right, and I think I can finally feel comfortable about digging into this little F***er that's been my nemesis for months now. So dear Sir, again, please know that my gratitude is limitless at the moment for you and your valuable time that you've freely shared here .. I truly and deeply appreciate you and your efforts along with your ability to explain it so even an idiot artist completely ignorant of any technical knowledge and skills like myself could understand. It clicked ... and I bet dimes to donuts I kick this things arse now, I just know it!! Thank you SIr!!! ✌️

Boy You Rock !!!!! you're naturally informative and clear in your explanation and i agree with the other comments you should be teaching.

This is one of the best video to simplify a audio amp out transistor thanks a lot u couldn't have made it any easier thanks again all thumbs up love the video

I am very impressed with your skill at teaching something that you yourself had only just learned. We the audience were clueless that you were new at this until you admitted it. Thank you for taking the time to make such a great and helpful video covering a subject that you have obviously discovered that is rarely broached yet needed to be covered.

Where you think you talking alot, and making no sense, you've just helped someone who listen alot to music but couldn't tell you why something has blown, and now I'm using TOUR knowledge you've shared to go and tackle a crown xti amp, that starts up then shuts down!!! So THANK YOU

That was the best explanation of a transistor I've ever heard! I've been learning about this stuff for several years and never felt I understood transistors as well as I do now. You've earned a sub for that alone

The lights just went on. This is the first time that I’ve literally understood how a transistor or indeed an amplifier works. Well done and thanks.😮😊

Absolutely great video.. you are a natural teacher and excellent at explaining stuff. Thankyou so much .. please make more.. ill bet you’d be really popular if you had a repair channel on here..excellent stuff! Not long not boring always moving forward in a way that makes sense. The transistor explanation was excellent and building from there was very informative .. thx again

I loved this video!!! I watched it right to the end and I learned a lot. I am a newbie at this field but dabbled with it a long time ago. I have the same amp, it's great a real work horse. You are a really good teacher and I hope to see more of your videos. You have a knack of explaining things that keep me and hopefully others focused to the job. Thanks again and take care.

You measured the Emitter and Base. Your Collector-Emitter idea is correct, but this time you got lucky with your diagnosis.

When I brought my amp in for service I mentioned that it was blowing fuses. The tech just said "Probably a transistor". He was right and it cost me $85. Your video explains perfectly how he would've known what was wrong and now I have a bit more knowledge. Thanks!

Dude. You definitely did not make a fool out of yourself. Your explanation put me on the right path for me trying to fix my reciever. It is not the same but it works the same. Thank you very much. You rock!

Excellent Video ! Like you I have searched hours to try and find enough info to try and track down faulty components in an Amp. Most of the ones I have found assume that you are already something of an electronics expert, so don't give such a good and detailed explaination as you have here. Can't praise you enough, but my thanks.

I watched several videos on fixing electronics and this is hands down the best one yet. So much valuable information. Spoke in plain english, not some text book confusion. Thank you!

Just FYI, that’s not a “1” on the multi-meter. It’s an “L”. Some meters will say “OL” which stands for “out of limits”. Means the resistance is outside the limits you’ve chosen to test because the two probes aren’t actually being connected through anything - cuz the fuse is blown. If a connection is made between the two probes THROUGH the fuse it will show the value of resistance in the object that’s being used to bridge them together. Good video.

Seriously thank you thank you thank you more times than I can say. I’ve had my kenwood stereo system for so long and the power amp recently ‘shut off’ ( no signal lights or sound going to speakers) and if not for the video I would’ve have had to spend 100+ on a new one or having someone else repair it so again thank you so much dude. 5 years later and literally your still the only video online I can find that explains this in a way someone who grew up just doin it myself and not knowing professional terminology can understand 😂😂

Brother, you brought back memories of my High School Electronics classes, and you're probably better at electronics than I am. Ill tell you one thing tho. You refreshed my memory on the transistor and resistor topics. So thank you for taking the time to make this.

Dude that was the most comprehensive amp repair I've ever seen Outstanding

Dude, I am extremely thankful that you put this video together!! I have a similar issue but I have just started down this long and dark path that lead me down to a rabbit hole I couldn't help but dive into! I have a board that keeps blowing a fuse on a bass amp that I don't have any of those round guys that you were showing I have these square ones that are on an aluminum plate and I want to say that they're bridge transistors, but I am not sure but there is solder missing on a couple of the points and I wanna say that is the problem. But I'm just not sure.

Thanks for posting this! Before I watched this, I’d never considered pulling a bad transistor and the amp will still work, albeit with less power output than before, but the point is, it’ll still work! I tried it on a vintage BGW amp I have with a blown channel, and transistors made of unobtainium, and it worked! I removed the same transistor from the opposite side, even though it was good, so both channels would have equal output, and Shazam! An amp that hadn’t worked in 20 years was back in service! THANKS again!😉😎👍🏻

You helped me fix my Sansui 881 and saved me hours! Thank you!

Bro! Best germanium amp fixing video on KZfaq, not long nor boring, exactly what one is looking when trying to troubleshoot and fix one of these things. Thank you very much for taking the time and effort of doing this for all of us! Cheers!

You did good, I understand more now then I did before, you explained it very well in layman terms, thank you for your time.

Thanks brother. I knew nothing about this circuit diagram but now I understand something new. Thanks for teaching me.

Thanks much for that mini-lesson. Having the correct schematic for the unit being repaired sure is helpful. Thumbs up.

Hey thanks! This video was actually super helpful. I've been wanting to get into fixing electronics for a while so I went and got myself a gig fixing amplifiers and speakers for a local pawn shop today. I have no clue what I am doing and I like the way you explain things and it wasn't boring at all!

Very good presentation and explanation of the circuitry. I've dabbled with electronics about 40 years ago and you brought back memories of those days. Thanks

This may turn out to be practically useful for me; but even if my problem is actually something else, I GREATLY appreciate the time and effort you spent explaining the relationship these parts have to each other and the schematic. Thank you :) I am now far better able to understand what all the forum "experts" I have tried reading were waffling on about. *Note to "experts":* There's no value in explaining something using terminology that only another expert understands, since they already understand it! Take a leaf out of this guy's book. Thanks again TeDubbs. Really. Much love :)

I'm far less knowledgeable than you are, but wasn't totally lost. Thanks for the help. I'm here because I have several 70s receivers that have problems. Most all don't put out sound from the right speaker, across all channels. So, no stereo but I can play both speakers if I use 2 channels. Your video was the first to explain what was wrong(I guessed correctly, but didn't know the terms), why and how, and also explained how to fix it as well. Thanks a million!!! If you have time, I have more questions so I don't ruin a couple really nice amps, or rather "stereo receivers"... I have a 1970 Kenwood kr-6160, and my favorite and cult following unit, the 1976-1979 Sansui 9090db. A few others of the Era, but these are my favorites.

I like that you literally explain what the difference is of each channel was and where that that break comes into I didn't really fully understand the admit her the bass and The Collector and what the percentage of them actually working is until you fed me this information I think you would be an excellent teacher for anyone

I can't imagine this has not been pointed out yet but the solder pads on the board connect to the Base and Emitter. The Collector is the big metal case on the other side. On this model QSC amp the collectors are grounded directly to the aluminum heatsink. Most amps isolate the collector with an insulator, some of which require thermal transfer compound, others do not. It is also quite common for other components to short (or open) along with the power transistors. While I understand that you are trying to help people out and save them money, you are in effect giving them just enough information to possibly do serious damage to their amp or to themselves in the process. It isn't always as easy as it looks folks.

An amazing insight into what goes on with a fault in a Amp, very valuable info, most grateful.

I really like that you took the time to explain all this. Great video.

I think the first thing I would do before any thing else is to blow out all the dust and dirt. Quite often overheating is the issue leading to blown transistors. Air flow is very important if the amplifier is driven hard. Once fixed any air filters should be well cleaned, check the fan, apply a little oil if needed. If you don't do this, it will probably blow up again.

Very nice job. You taught me more about troubleshooting than I've learned in any other video. Besides that, the transistor function finally make sense!!! Thank you!

while i was listening to your video i was fixing a jb systems vx400. or trying to fix it. i'm no electronics guy. it is because of guy's like you that i can learn how to fix things !!! thank you very much !

It's a very good video. I love when someone explain something even small details it help a lot to have an idea on that field. Especially when you don't know anything about it. Thank you very much. 👍

Thanks Most well explained (in simple terms) video I came across so far on this topic.

I've been waiting for a video like this thank you! Repairing the things you have rather than throwing them out and buying new; is a great thing. People who help others to do this are great people. P.S. If you aren't sure what a boring video is, I can give you some links...trust me, your informative video is NOT boring :)

Thank you for taking the time to create this clear and simple explanation. It helped me. Kudos.

Easy to understand straight to the point great vid

Thank you for this detailed explanation. I'm currently debugging a jukebox amplifier, and this has given me some good insight on what I need to do.

Will give this a try. Whether or not it works to diagnose if one or more output transistors is blown on my amp, I learned useful info. Thanks much. Great video.

Awesome vid .. I have a QSC PL9 and one of the channels stop working. I was about to bring it for service and like you already know, it is an outdated AMP which would cost me $$$$$ then who to tell, similar issues can resurface again ... knowledge is POWER. Thank you for such detailed vid for DIY like myself ... you just saved me $$$$$$$ for now :)

Thanks for a very quick and simple explanation. Easy to understand and very helpful!

Great, useful straightforward and concise explanation. Awesome dude!

Driving a speaker load with a guitar cable is always s bad idea. Good clarity on your explanation of tracing out the faulty output transistor. Did you know that dust becomes conductive after heat and current flow hit a trigger point? That sends the DC rail voltage where it should never go...avalanche voltage breakdown followed by shorted output devices. Clean away the dust and check the mica wafer for cracks. Replace the wafer if it looks compromised.

Wow thank you you explained that very well I've now fixed four of my blown amps cheers buddy. 👍🍺

Excellent video ! Like you i've done a lot of searching to get enough info to track down faulty component(s)i in an Amp. Most of the ones I have found assume that you are already something of an electronics expert, so don't give as good an explaination as you have here. Can't praise you enough.

thanks for explaining this video so well. been trying to understand Amp circuits and how amps work and your video was by far the most helpful

Buying a new stereo amp is difficult today, all you find are 5.1 and up surround amps with more than two speakers, so repairing my Sherwood receiver was my best option, I found thst it uses a combo of B1560/D2390 transistors, I found a set of 5 pairs on e-bay for less than $15.00, this vdeo was very helpful in finding the fault quickly, thank you.

Thank you for explaining this in good detail. Very easy to understand, keep up the good work.

Thanks for a great and informative video. Extremely helpful information that was very clearly explained.

Man this is the way I wanna be taught!! By a guy who learned it himself and can explain it in simple language. This was great. Pretty sure thats what I got going on here. Not sure Im gonna do it myself yet. Not the best with a solder gun But I really wanna learn this stuff and your explanation was great. Just like everybody else said great job.

Thanks for your interesting and informative video! I'm feeling ready to take on my bass guitar amp now!

Like the others before, I enjoyed all of the video. Very clear in presentation and explanation. The weird bit for me was knowing the there was a base, emitter and collector is one thing, but on this type of heat generating transistor, the two central pins that are soldered to the board could be one or the other as I believe the 'base' is part of the chassis/mounting. Thank you for taking the time. The video also has shelf life too! ;)

Really helpful, illustrating what I need to look for and why. Thank you, you do a wonderful job.

Googling for help trying to figure out why I've lost my center channel, left back, left surround and right surround channels and came across this. Fixing it myself is out of the question but nice to see that it's hopefully going to be a simple fix. Thanks.

Thanks, I learned something and I haven’t seen any showing this before, something I wanted to understand for a while now. So, kudos!

Not boring at all u helped me to understand the basics which drive me to want to learn more about what I love to do best for a hobby ..thanks and do more tutorials .

very good accurate basic description. nice. -- the last part that analyzes the circuit is very good

What steevie-joe said! I have been watching a lot of videos lately on electronic repairs. You made it sound easy for this dummy. Great video. Only suggestion would be to hold pointer still instead of bouncing around. Great camera work, too.

Stumbled upon this video - GOOD JOB! One thing I can suggest - along with working one-handed, use a wooden dowel or chopstick to poke around bitey electronics. A drumstick works as well, until your kid steals it. :D

Exlnt video mate, This a great primer for understanding transistors and looking for something other than a blown cap.

Awesome Video! Thnx! You are not boring at All! The best explanation of fixing Amps! Now I can fix my Amps! Keep those Videos Comming! :-)

Thanks, dude. Party on. Great explanation. I'm way ahead of where I was with the understanding that I have a ways to go too.

Thanks so much for teaching in such great detail and doing all that research. I am going to attempt to fix the 1 non-working channel on my amp and see how it goes.

Excellent video,well detailed.I learned a lot from it.Thanks

Dude great video excellent explanations and very thoroughly thought out

Awesome! Thanks for the video. I've always been interested in electronics, and unfortunately did exactly what you said not to do. I replaced a fuse and turned my amplifier back on. I have a Mackie M2600. When I went to turn it off, I didn't hit the switch all the way. It shut off for a split second, and came back on. It tripped the breaker in the basement. When I turned it back on, it powered up for about 6 seconds, and then the fuse blew. I never had any problems before, and knowing it was a slow blow fuse, I ASSumed that was the only problem. After replacing the fuse, it powered back up and stayed on, but when I went to put power to it, the "protect" and "short" lights lit on channel 1. It was fine at low volume, but given some power, both lights lit up. From what you explained in the video, and what I've experienced, I'm guessing a short between collector and base - and who knows what other damage it may have caused! Looks like I'll be taking this one to the shop, but the video was still very informative, and I now I know what a transistor does!

I have a probably identical situation with a Dynacord amplifier and I will try to examine it according to your explanation of this. Thank you very much.

pretty great video, bro. appreciate it.

THANKS! Awesome, simplied AND explained why the difference of .5 OHMS exists - I thought I had MOSFETS on my Peavey PV1500, but they are just Bi-Bolar Transistors too.

Awesome video man. Thank you for posting. Just had my Bryston 4B make a few pops and fizzles last night and Im hoping its just replacing some transistors, resistors, and the fuse. Thanks again.

Thanks for this video,at last safter a lot of searching ,s omthing in depth and useful. I have learned a lot .

Thank you for an excellent video. Perfectly explained and completely understandable!

Good video! Extremely informative. Thanks!

Well done! Helped me greatly! Thank you.

You rock that was totally helpful I also saw the part where you fixed in old speaker that was great thanks a lot have a great day

I agree w/ @stevie-joe.... I'm not sure if It's your timing in showing the schematic with it's real life representation, or your candor and humility, but, I could immediately ID the components in my amp,(as I remembered them) and "follow" what I saw here in that context. I watched this BEFORE I attempted the repair because usually I have to watch videos 10 times with frequent pauses and a hot soldering iron burning daylight. I feel comfortable to start this repair without having to have somebody "hold my hand" from the information I got here.. Thanks

Yeah great video. I like to collect stereo gear, find stuff at garage sales and such. And often you can find something inexpensive, but does have a small problem. Or your cat can knock over a cup of water onto your turned on beloved amplifier and well you know. So I'm getting into learning how to fix the equipment instead of tossing into a land fill. Especially my beloved amplifier/AV receiver which was quite good, and would be expensive to replace with a new amplifier/receiver of the same quality today. Like $1,000 or more.

Thank you for your effort...A word of caution though, replacing the defective output transistor without checking its forward bias whether it's within limits or not will allow the audio amp to function again but for more or less 15 minutes only because the transistor will overheat and be defective again.

excellent video. You didnt use too much jargon, or when you did you explained what it all means. I really appreciate having some help thats explained in laymans terms. Thank you, will tear into my amp now feeling more confident..

excellent video, thanks for taking the time!

that's the dirtiest amp I ever saw, but good job explaining this man, appreciate it!

love the small talk i really understand whats going on the way you tell it.

I wish I came across this video before, great explanation and learned a lot

Good video. Learned a lot. Thanks. Wish you post more videos.

Hey man keep it up I can actually understand what you were saying. Keep learning so you can teach me more thanks a lot

This video is brilliant, thank you.